title: The clinical assessment of protease-activated receptor-2 expression in inflammatory cells from peripheral blood and bronchoalveolar lavage fluid in idiopathic pulmonary fibrosis.
abstract: BACKGROUND
  Idiopathic pulmonary fibrosis (IPF) is a lethal pulmonary fibrotic disease. In general, the exaggerated activation of the coagulation cascade has been observed during initiation or maintenance of the fibrotic disease. In our recent study, immunohistochemical expression of protease-activated receptor-2 (PAR-2), which plays a key role in coagulation cascade, was observed in surgical specimen of IPF patients, and associated with poor clinical outcome. The aim of this study was to evaluate the overexpression of PAR-2 in inflammatory cells from peripheral blood and bronchoalveolar lavage fluid in IPF patients.
  
  
  METHODS
  From May 2011 to March 2012, IPF patients and controls were enrolled in Seoul National University Hospital. Peripheral blood and bronchoalveolar lavage fluid were collected for analysis of PAR-2 expression. Flow cytometry and reverse transcription polymerase chain reaction were used for PAR-2 receptor and mRNA assessment.
  
  
  RESULTS
  Twelve IPF patients and 14 controls were included in this study. Among them, flow cytometry analysis was conducted from 26 peripheral blood (patient group, 11; control group, 13) and 7 bronchoalveolar lavage fluid (patient group, 5; control group, 2). The expression of PAR-2 receptor was not different between patient and control groups (p=0.074). Among all 24 population, PAR-2 mRNA assessment was performed in 19 persons (patient group, 10; control group, 9). The mRNA expression of PAR-2 was not significant different (p=0.633).
  
  
  CONCLUSIONS
  In IPF patients, PAR-2 receptor and mRNA expression were not different from control group.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine and Lung Institute, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Young Sik
authors.initials: YS
authors.lastname: Park
authors.forename: Chul-Gyu
authors.initials: CG
authors.lastname: Yoo
keywords: Bronchoalveolar Lavage; Idiopathic Pulmonary Fibrosis; Receptor, PAR-2